AB0560 CLINICAL, SEROLOGICAL AND IMAGING CHARACTERISTICS OF LATIN AMERICAN PATIENTS WITH LUPUS MYOCARDITIS: A CASE-CONTROL STUDY
Authors: D. C. Quintero-González, J. Sanchez-Bautista, C. Agudelo, A. L. Vanegas-García, C. Muñoz, Y. Santamaria-Alza, A. Cardona - Cardona, M. Muñoz, G. Vásquez, L. A. González
Journal: Annals of the Rheumatic Diseases (2022)

Background Lupus myocarditis (LM) is an uncommon manifestation of systemic lupus erythematosus (SLE), with a prevalence of 9% that tends to be lower in recent studies; it can range from subclinical to life-threatening manifestations (1). The clinical and immunological characteristics of LM have not been established in Latin American patients. Objectives To determine the clinical, serological, and imaging characteristics of patients with LM. Methods We conducted a single-center, case-control study that enrolled hospitalized patients between 2012 and 2020 in Colombia. Fifteen LM patients (cases) were matched by age and sex with thirty non-LM patients (controls). Descriptive, comparative, and logistic regression analyses were performed. Results Patients with LM were mostly females (93.3%) with a mean age of 28.2 years. The major affected clinical domains associated was renal (80%). Myocardial involvement occurred after SLE diagnosis with a mean of 5.1 years. Dyspnea (73.3%) was the main clinical manifestation. Troponin was high in 92.3% and echocardiographic findings included decreased left ventricular ejection fraction (LVEF) in the 60% of cases (mean 40%), diastolic dysfunction (61.5%), left ventricular dilatation (53.3%) and global hypokinesia 35.7%. The most common valvulopathy was mild mitral regurgitation. Nine LM patients underwent cardiac magnetic resonance. In this modality, mean LVEF was 38%, increased regional intensity on T2-weighted images, increased myocardial potentiation ratio on T1, and non-ischemic enhancement (mainly epicardial) was presented on 85.7%, 60%, and 57.1%, respectively. All patients received glucocorticoids and cyclophosphamide. Comparisons of the demographic, clinical, serological between LM and non-LM groups are shown in Table 1. Table 1. Demographic, clinical and serological characteristics. Variable LM (n=15) Non-LM P-value Female 93.3% 100% 0.333 Age SLE 24.9 (SD 12) 28.3 (SD 13.9) 0.515 Clinical domains Cutaneous 46.7% 90% 0.003 Articular 60% 76.7% 0.245 Hematological 60% 83.3% 0.086 Serosal 53.3% 36.7% 0.227 Renal 80% 76.7% 0.560 Neuropsyquiatric 6.7% 26.7% 0.115 Vascular 13.3% 50% 0.017 PCR mg/dL 10.1 (SD 9.3) 2.8 (SD 4.6) 0.0004 Erythrocyte sedimentation rate mm/H 52.9 (SD 25.7) 43.9 (SD 32.9) 0.267 Creatinine mg/dL 1.4 (SD 0.9) 1.9 (SD 2.5) 0.294 C3 mg/dL 57.4 (SD 22.4) 86.2 (SD 29.9) 0.002 C4 mg/dL 9.6 (SD 8.3) 16.4 (SD 9.3) 0.009 Anti-dsDNA 86.7% 52.4% 0.034 SLEDAI score 14.7 (SD 5.7) 6.8 (SD 7.6) 0.0003 SD: Standard deviation Bivariate logistic regression showed that LM was independently associated with anti-dsDNA (OR 1.17, IC 1.04 – 1.31, p= 0.004), higher SLEDAI score (OR 1.17, IC 1.04 – 1.31, p=0,006), higher RCP (OR 1.21, IC 1.04 – 1.4, p=0.013), lower C3 (OR 0.96, IC 0.93 – 0.98, p:0,06) and lower C4 (OR 0.90 IC 0.82 – 0.99 P=0,036), highlighting its relationship with disease activity. Conclusion LM is a potentially severe manifestation and occurs in patients with higher disease activity, as was evidenced in the present study by low complement, anti-dsDNA and SLEDAI score. In the proper clinical context, noninvasive diagnostic tests should detect myocardial involvement in SLE. References [1]du Toit, Riette et al. “Outcome of clinical and subclinical myocardial injury in systemic lupus erythematosus - A prospective cohort study.” Lupus vol. 30,2 (2021): 256-268. doi:10.1177/0961203320976960 Disclosure of Interests None declared